African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6638

Full Length Research Paper

Variation of quercetin content in different tissues of Welsh onion (Allium fistulosum L.)

Xihuan Feng and Weixin Liu*
College of Horticulture, Qingdao Agricultural University, Qingdao, 266109, P.R. China.
Email: [email protected]

  •  Accepted: 03 September 2011
  •  Published: 12 November 2011



Due to its proposed potential role in reducing risk of cardiovascular disease and some forms of cancer, flavonol level in plants is an important trait. In this study, nine Welsh onion cultivars were grown in 2006 in Jinan, and six cultivars were grown in 2007 in Qingdao to study the distribution of quercetin (a flavonol) among different tissues of the Welsh onion. After harvest, quercetin levels in leaves, upper pseudo stems, and inner and outer rings of lower pseudo stems were measured for each cultivar. Large variations in quercetin levels were observed among cultivars. ‘Jilin Xiao Cong’, a local cultivar of Northern China, had significantly higher quercetin levels in pseudo stems (about 4 times) than the other cultivars in the Jinan trial (< 0.05). Leaves of ‘Zhangqiu Da Cong’ and ‘Shi Guo Yi Ben Tai’ had higher quercetin levels than those of the other four cultivars in the Qingdao trial (P < 0.05). Leaves contained significantly higher amounts of quercetin than pseudo stems (P < 0.05). The inner core tissues of pseudo stems had significantly higher levels of quercetin than the outer rings (P < 0.05). The results indicated that intake more leaves of Welsh onion may contribute a significant amount of flavonoids to one’s diet and health benefits. The results of this experiment are useful for plant breeders who are interested in improving this trait in Welsh onion.


Key words: Allium fistulosum L., Welsh onion, flavonols, quercetin, variation, spectrophotometry.